Fry in butter diced champignons, boiled chicken fillet, and calf tongue. Pour the vinegar, salt, pepper, and simmer for a couple of minutes.
Then pour lightly beaten eggs, salt, pepper, season with sugar (a pinch is enough) cook over low heat.
Heat the croissants in the microwave, in the oven or in a frying pan, cut the side of the croissants and fill with an omelet.
Complements the breakfast perfectly with a full and rich taste of the coffee.